ZOOLOGTSCHE MEDEDEELTNGEN
286
XI. -
— DEEL
XVII.
ON SACCULIN A P U N C T A T A , A NEW SPECIES FROM J A P A N
BY H . B O S C H M A . (WITH 2 TEXT-FIGURES).
T h e present paper contains the c h i e f p a r t i c u l a r s o f a specimen i n the
collection
hitherto
of
the U n i t e d States N a t i o n a l M u s e u m ,
described
species
differing from
the
of Sacculina i n its a n a t o m i c a l characters a n d
i n those of the c u t i c l e of the m a n t l e .
Sacculina punctata nov. spec.
Kaseda, Satuma, Japan, T. Urita coll. et don., 1 specimen on Plagusia dentipes
de Haan, U. S. N. M. N°. 48337.
D i a g n o s i s . Testes
outside
The
almost
e n t i r e l y i n the posterior part of t h e b o d y ,
t h e v i s c e r a l mass, vasa deferentia p a r t i a l l y i n the v i s c e r a l mass.
two testes
w e l l developed,
less g l o b u l a r or somewhat
completely
compressed,
separated, f o r m i n g more or
wide
sacs, w h i c h are connected
w i t h the w i d e vasa deferentia b y a short, n a r r o w tube. C o l l e t e r i c g l a n d s
w i t h n u m e r o u s b r a n c h e d tubes, a p p r o x i m a t e l y i n t h e c e n t r a l part of t h e
lateral
surfaces
of
the visceral
mass.
External
cuticle
of t h e m a n t l e
w i t h o u t excrescences, or covered w i t h s m a l l r o u n d i s h p a p i l l a e , o r p r o v i d e d
w i t h i r r e g u l a r o u t g r o w t h s w h i c h g i v e i t a more or less ragged appearance.
Surface
of the e x t e r n a l
cuticle w i t h
distinct l i t t l e areas w h i c h have a
diameter v a r y i n g f r o m 7 to 18 jCt. U s u a l l y i n these areas there i s a c e n t r a l
column
consisting of c h i t i n
which
differs
i n s t r u c t u r e f r o m that of i t s
s u r r o u n d i n g s . I n t e r n a l cuticle w i t h n u m e r o u s r e t i n a c u l a , arranged i n r o w s
on i t s surface. E a c h r e t i n a c u l u m consists of a s i n g l e s p i n d l e w h i c h has a
l e n g t h of 7 to 12 p.
The
specimen
is c o m p a r a t i v e l y
l a r g e , its b r e a d t h (greater
is 2 3 m m , i t s h e i g h t (the distance f r o m t h e s t a l k to t h e m a n t l e
diameter)
opening)
is 16 m m , a n d i t s t h i c k n e s s 6 m m . T h e a n i m a l is more or less k i d n e y shaped,
the stalk being
found
at t h e concave side, t h e m a n t l e o p e n i n g
at t h e c o n v e x side.
T h e p e c u l i a r f o r m a n d s i t u a t i o n o f the male g e n i t a l organs i s represented
i n fig. 1. T h e first section (fig. la) shows the testes, w h i c h are contained
in
t h e posterior
second
section
region
(fig. lb),
of t h e b o d y , outside t h e v i s c e r a l mass. I n t h e
a more
v e n t r a l one t h a n the former, t h e w i d e
vasa deferentia are v i s i b l e . T h e l a t t e r are connected w i t h the testes b y a
short n a r r o w
c a n a l w h i c h possesses a c h i t i n o u s i n t e r n a l l a y e r . I n t h i s
r e g i o n t h e m a l e g e n i t a l organs show a d i s t i n c t c u r v e , as t h e d o r s a l part
RIJKSMUSEUM
of
the
vasa deferentia
VAN NATUURLIJKE
lies b e h i n d
the
HISTORIE
—
287
LEIDEN.
v e n t r a l part of the testes
(the
r e g i o n of the s t a l k is the posterior part of the b o d y ) . I n t h i s section the
whole
of
the m a l e g e n i t a l organs s t i l l lies outside the v i s c e r a l mass.
A
s t i l l m o r e v e n t r a l section (fig. l c ) shows that g r a d u a l l y the m a n t l e c a v i t y
is
e x t e n d i n g f a r t h e r towards the posterior p a r t of the b o d y , so that t h e
m a l e g e n i t a l organs become a p a r t of the v i s c e r a l mass. T h e most v e n t r a l
F i g . 1.
Sacculina punctata, longitudinal sections of the posterior part of the body,
a from the dorsal region, each following section nearer to the ventral region than its
predecessor. ce external cuticle of the mantle; mc mantle cavity; t> testis; vd vas
deferens. X
12y
part
of
the
(fig. I d ) ;
>
vasa deferentia
here
the
t
is f o u n d at each side of the v i s c e r a l mass
mantle cavity
n e a r l y reaches
the
posterior p a r t of
the b o d y .
As
are
i n most
fairly
of
the l a r g e r species of the genus the c o l l e t e r i c glands
l a r g e . T h e y are present i n the c e n t r a l r e g i o n of each l a t e r a l
surface of the v i s c e r a l mass, and c o n t a i n n u m e r o u s b r a n c h e d
The
e x t e r n a l c u t i c l e of
the
tubes.
m a n t l e varies i n t h i c k n e s s f r o m 40 to
288
ZOOLOGISCHE MEDEDEELINGEN
— DEEL
XVII.
F i g . 2.
Sacculina punctata, a, section of the external cuticle; b, somewhat oblique
section of the external cuticle from another part of the mantle; c, and d, surface
view of two different parts of the external cuticle; e, part of a row of retinacula on
the surface of the internal cuticle. X
^30.
RIJKSMUSEUM
VAN NATUURLIJKE
6 0 (JL a p p r o x i m a t e l y . I n different
HISTORIE — LEIDEN.
289
parts o f t h i s c u t i c l e the areas w h i c h
are found o n i t s surface have a different s h a p e : t h e y m a y be m o r e o r less
polygonal
central
(fig. 2c) o r h a v e a n i r r e g u l a r sinuous
column
which
consists
of a different
c o n t o u r (fig. 2d). T h e
kind
o f c h i t i n u s u a l l y is
d i s t i n c t l y v i s i b l e i n surface v i e w . I n stained sections these c o l u m n s often
are not v i s i b l e ( f i g . 2 a ) , i n other parts o f the c u t i c l e , e s p e c i a l l y w h e n t h e
sections are s o m e w h a t oblique (fig. 2b) t h e y are d i s t i n c t , e s p e c i a l l y i n t h e
upper h a l f of the cuticle.
T h e retinacula are arranged i n broad
internal
cuticle. Between
these
bands
o n t h e surface o f t h e
bands, w h i c h l i e at some distance
from
each other, not a s i n g l e r e t i n a c u l u m is f o u n d . A p a r t o f such a b a n d i s
represented
i n fig. 2e, the r e t i n a c u l a , each o f w h i c h consists of a s i n g l e
s p i n d l e , occur here r a t h e r
In
some respects
punctata
easily
crowdedly.
t h e s t r u c t u r e of t h e e x t e r n a l c u t i c l e o f
Sacculina
i s s i m i l a r to that i n S. sulcata V . K . & B . T h e t w o species are
d i s t i n g u i s h e d b y the different shape
I n S.punctata
o f t h e m a l e g e n i t a l organs.
both t h e testes a n d t h e vasa deferentia h a v e a w i d e l u m e n .
O n t h e o t h e r h a n d t h e testes o f S. sulcata possess a v e r y n a r r o w l u m e n ,
and its vasa deferentia are narrow canals.
19
(SI—10—1934)